The European Union

The European Union consisted of 25 countries. It was a way to stop fighing aginst each other. before the union countries like France and Germany fought each other three times, with terrible loss of life. After this and many other events countries in europe dicided to make the union to preserve long lasting peace.
Now that this 25 countries are bond together economically, politically, socially, and militarily, the chances of these nations going to war again is very little.
Before the Union for travelers to go from one country to and other they need passport check, they also needed to change their money every single time. But after the Union, it was decided to use only Euros which is the current money. today euros are traded more than the the US Dollar.